schrader et a



Oct. 23, 1928. 1,688,357

H. SCHRADER ET AL SULPHUR OF A HIGH DEGREE OF DISPERSION AND PROCESS OF PREPARING SAME Filed Aug. 14, 1924 w? WM M THEIR ATTORNEY HANS SGHBA'DER, ESSEI LBEEDENEY, A ID I-IA BOLD GERMANY.

Application filed August 14-, 1924, No 731.987, and in Germany August 16, 1923.

This invention relates to the preparation of sulphiu' ot' a high degree of dispersion.

Sul hur in finely divided or powdered form is require 1 in many branches of industry, for instance,i-. agricii ure :tor combatting fungi, especially in vineyards and in the rubber industry.

By the l-rnown methods of manufacture sulphur can be obtained in powdered form in two different ways. In one case mechanical means are employed, crystalline sulphur being ground and subjected to air flotation. In the other case the sulphur is obtainedin fine state of subdivision by sublimation. Both methods produce finely subdivided sulphur, but it has been impossible to increase the degree oi fineness by any further improvement or modification oi these methods. There is also a so-called precipitated sulphur on the market which is produced by decomposing polysulphid-es. ts degree oi dispersion is generally higher than that of the two previously mentioned products. However, 0wing to its considerably higher cost, it is not utilized to appreciable extent in industry and agriculture. industry and agriculture require lar e amounts of sulphur having the highest possible degree of subdivision at a cost which does not prohibit its use.

The product or" the present invention tulfills this requirement. According to the process of the present invention sulphur vapors are dispersed during sublimation to a exceedingly tine fume by means of pure ammonia or ammonia diluted with another inert or non-oxidizing gas, such as nitrogen, and the resulting sulphur fume is separated from the dispersing gas as a powder having a high degree of dispersion.

In order more clearly to understand the invention, reference is made to the accompanying drawings which illustrate diagrammatically by way of example one form of apparatus suitable for carrying out the process.

The method at Fresenius and Beck see Zei .c' ir Analyt-ische Chemie, vol. 42, page 21, (1908). is described as follows;

l Ve used the sulturimeter of Johannes Greiver Fabrik fur Pracisions-Glasinstruinente, in Munchen. It was made according to the directions of. Portele and consisted of a glass tube, oii about cm. in length,

AU provided with a ground in glass stopper and a scale from O to 100. The length 01 the tube to 10G marl; was 175 nun, the length of the ght part the tube from the 1 0 marl: to the 100 mark was min, and toe interior d net-er of the tube was 12.68 mm.

The s ur powder to be tested was put h a 1 sq. mm. mesh sieve in order to up the hu; i which always form in s irur on long standing. litter sieving and ug well 5 gr. were weighed out on a watclnglass to 0.1 mg. The sulfur was brought into the suliurimeter with the aid of a sheet oi cardboard and a brush. Then the apparatus was filled to about 1 cm. over the 100 marl: with ether and strongly shaken tor about one minute in order to thoroughly b l sult'ur. The apparatus is now i no the strongly shaken in a vertical position for exactly seconds and then lowered in a vertical position into a beaker of water at 17.5 without touching either the walls, the bottom, or the thermometer. The sulfur settles to the bottom quite rapidly. When the height of the sulfur no longer changes and the overlying ether appears completely clear, the height of the sulfur is read on the scale (to one half scale degree). The number thus read gives the degree Chancel directly.

Referring to the drawing, V is a fan which serves to circulate pure ammonia or ammonia diluted with another gas in a closed cycle in the direction indicated by the arrows. The gas is forced through the ejector E and passes as a strong current through the neck of the retort R. The sulphur vapors issuing from the retort R are dispersed by the gas current and simultaneously cooled, and the fume produced is caused to enter into the chamber K where the sulphur is separated out. This separation can be elfected in a known manner, for example by simply allowing the sulphur to deposit or by electrical precipitation.

The degree of dispersion of the sulphur may be influenced by varying the relative quantities of the gas and the volatilized sulphur supplied to the ejector.

The sulphur produced by the present process as compared with the powered sulphur products hitherto on the market is distinguished by its high degree of dispersion and its considerably greater reactivity, said sulphur having a degree of dispersion which is far greater than that of the best flowers of sulphur or air-floated sulphur or even the precipitated sulphur.

lllll ing the degree of dispersion according to the I method 01' Fresenius and Beck, the dispersed sulphur producec according to the present process shows 7090 Chancel as compared with the finest products hitherto on the 111211- ket which show shout 35 Chancel.

Claims:

1.'Process for the production of sulphur ofa high degree of dispersion which consists in dispersing sulphur vapors by means of :1

t as corn 3ris1n ammonia and se )urzttim the sulphur from the resulting fume.

2. Process for the production of sulphur of a. high degree of dispersion as defined in claim 1, in which the degree of dispersion of the sulphur is determined by regulating the quantity of gas used in dispersing a unit quantity of sulphur vapors.

3. Process for the production of sulphur of a high degreeofdispersion which consists in simultaneously cooling and dispersing" sulphur vupors'by meansoife of a gas conr prising ammonia, and thereafter collecting the finely divided sulphur.

In testimony whereof \V ufiiX- our "natures.

DR. l-IANS SGHRADER. DR. ING. HAROLD SCHOELLER. 

